I have two Linux VMs, let's call them VM1 and VM2. I have on VM1 an 80 Gb file. When I try to transfer this file from VM1 to VM2 the transfer rate is almost 256 Mb/s.
scp 80Gblargefile VM2:/home/myuser
Then I remove the file from VM1 and, always in VM1, I try to copy back it from VM2:
scp VM2:/home/myuser/80Gblargefile .
In this case, the transfer rate is 46 Mb/s.
The transfer always occurs on the same network interface.
I would like to understand if it is normally a situation like this. If no, what I can do to debug the problem? I suspect there is a problem with a kernel parameter or network configuration. But I don't know what to check.
I verified with traceroute there is one hop between the two VMs. Moreover, I tested the bandwidth with iperf From VM2 (as a server) and VM1 and I got:
[ ID] Interval Transfer Bandwidth
[ 4] 0.0-10.0 sec 14.8 GBytes 12.7 Gbits/sec
I did also the reverse:
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-10.0 sec 14.7 GBytes 12.6 Gbits/sec
